During his time at Microsoft, Newell, along with fellow co-worker Mike Harrington, were impressed by computer games that were being released in the mid-1990s, such as id Software's Doom and Quake. Fully convinced that video games were the future of entertainment, and intrigued by the prospect of having his own game development studio, Newell, along with Harrington, left Microsoft in 1996 to found Valve, of which he remains president.

In 2007, Newell openly expressed his displeasure over developing his software for gaming consoles, particularly the PlayStation 3. In regard to the system, Newell was once quoted as claiming that developing processes for the console in general was "a waste of everybody's time"[9] and "a disaster on many levels ... I'd say, even at this late date, they should just cancel it and do a do-over. Just say, 'This was a horrible disaster and we're sorry and we're going to stop selling this and stop trying to convince people to develop for it'."[10] Nevertheless, at Electronic Entertainment Expo in 2010, Newell appeared on stage at Sony's keynote; while acknowledging his past outspoken comments on console development, he discussed the open nature of Sony's PlayStation 3 platform, and announced Portal 2 for the console, remarking that with Steamworks support it would be the best version for any console.[11] Newell has also criticized the Xbox Live service, referring to it as "a train wreck".[12] He was also critical of Microsoft's Windows 8 operating system, calling it a "catastrophe" and "a threat" to the open nature of PC gaming.[13]

In December 2010, Forbes named Newell as "A Name You Should Know", primarily for his work on Steam having partnerships with multiple major developers.[14] In March 2013, Newell received the BAFTA Fellowship award for his contributions to the video game industry.[15] In October 2017, Forbes listed him among the 100 richest people in the United States, with an estimated net worth of US$5.5 billion.[1][16]

Personal life

Newell formerly suffered from Fuchs' dystrophy, a congenital disease which affects the cornea, but was cured by two cornea transplants in 2006 and 2007.[17] He married Lisa Mennet Newell in 1996, whom he has two children with.[18][19][20] The birth of his son Gray in the late 1990s served as inspiration for the final boss of Half-Life, as the couple considered childbirth to be the most frighting thing they could think of at the time.[21]

Within the gaming community, he is jokingly known as "Gaben", which is derived from his work email address.[25] Newell stated that he has tried to grow into his public image: "They hug me when they run into me. I'm not a hugging person, but that's what they want. I was with my kids the first time that happened in public, and my kids were pretty cool with it. But I wasn't. 'Dad, roll with it.' Even now, I'm learning from our customers."[26]